mettle sendportal APIv1 Webhooks mailjet missing authentication

published 2026-07-09 4 mo ago modified 2026-10-25 14 d ago also EUVD-2026-42624

cvss: 6.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.8%; EPSS 0.8% chance of exploitation in 30 days, percentile 55%
public exploits: 0; none known

A vulnerability has been found in mettle sendportal up to 3.0.1. This issue affects the function sendgrid/postmark/postal/mailjet of the component APIv1 Webhooks. The manipulation leads to missing authentication. The attack is possible to be carried out remotely. The exploit has been disclosed to the public and may be used. The project was informed of the problem early through an issue report but has not responded yet.

CISA SSVC

Exploitation: Proof of concept is public
Automatable: yes
Technical impact: partial
Assessed: 4 mo ago (2026-07-09)

Exploit prediction

0.76% chance of exploitation in the next 30 days, higher than 55% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/mettle/sendportal/issues/340 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	6.9	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
CNA	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L/E:P/RL:X/RC:R
CNA	3.0	6.5	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L/E:P/RL:X/RC:R
CNA	2.0	6.4	AV:N/AC:L/Au:N/C:N/I:P/A:P/E:POC/RL:ND/RC:UR
CNA	4.0	5.5	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CNA	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
CNA	2.0	6.4	AV:N/AC:L/Au:N/C:N/I:P/A:P

Affected products

mettle sendportal

Classification

Weakness

CWE-306 Missing Authentication for Critical Functionality
CWE-287 Improper Authentication

References

github.com /mettle/sendportal/issues/340
exploit, issue-tracking
vuldb.com /vuln/377118
vdb-entry, technical-description
vuldb.com /vuln/377118/cti
signature, permissions-required
vuldb.com /cve/CVE-2026-15192
third-party-advisory
vuldb.com /submit/851624
third-party-advisory
github.com /mettle/sendportal/
product

Sources

CVE List CVE-2026-15192
NVD CVE-2026-15192

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary